1. Field of the Invention
The present invention relates to an information recording apparatus, an information recording method, an information recording medium, an information reproducing apparatus and an information reproducing method and is applicable to an optical disk system by, for example, a compact disk or the like. According to the present invention, in the case in which with regard to a defect having a size by which at least main data can be reproduced correctly, by allocating 1 bit of sub-data to a pit row or the like having a predetermined length or more such that the sub-data can be reproduced correctly, when data or the like related to copyright is recorded by partial change of pit shape or the like, the data can be reproduced with certainty without repeatedly recording the data.
2. Description of the Related Art
Conventionally, in a compact disk, there are recorded signals utilized by the user such as audio signal, TOC (Table of Contents) and the like in a program area and a read-in area and there is formed an area of recording IFPI (International Federation of the Phonographic Industry) code on an inner peripheral side of the read-in area.
Here, IFPI code is a code capable of confirming maker, production site, disk number or the like by optical observation and in the case of a compact disk, illegal copy of pirated edition or the like can be discovered by confirming the code.
In the meantime, when a compact disk of illegal copy can be detected automatically by a compact disk player, it seems that various measures can be taken with regard to illegal copy of this kind and right of a copyright owner can be protected effectively.
In this case, although it is conceivable to detect illegal copy by utilizing IFPI code, in the case of IFPI code, the code is on the premise that the code can be confirmed by optical observation and accordingly, when there is constructed a constitution in which IFPI code can be confirmed by a compact disk player, the constitution of the compact disk player becomes complicated. Further, IFPI code per se can be forged since the code can be confirmed by optical observation and in this case, after all, illegal copy cannot be determined.
With regard thereto, as proposed, for example, Japanese Patent Application No. 288960/1997, Japanese Patent Application No. 34837/1997, Japanese Patent Application No. 332222/1998, Japanese Patent Application No. 371795/1998 and the like, when data or the like related to the copyright is recorded by partial change of pit shape such that no influence is effected in reproduction of audio signal, such an illegal copy can be detected with certainty.
However, in the case in which data or the like related to copyright is recorded by the partial change of the pit shape, there is conceivable a case in which the partial change of the shape is difficult to detect owing to a defect of the compact disk. Thereby, in the case of the method, the certainty needs to establish by repeatedly recording the same data.